GEOL- Ch5 Sedimentary Rocks Quiz

As sea level rises, depositional environments shift inland with the advancement of the sea across a region. This results in shallow marine deposits on top of transitional or terrestrial sedimentary deposits. This is known as what type of event?

• regression

• flooding

• progradation

• transgression

Assess the sediments in the figure below and identify which would most likely lithify into a shale?

• C

• D

• B

• A

Chalk is considered a biochemical sedimentary rock because

• It’s a carbonate precipitated from ground water

• It's a mineral not a rock

• It’s an organic-rich sediment deposited in wetlands

• It's a carbonate that formed from the calcium-rich skeletons of microorganisms that had accumulated on the seafloor

Clastic sedimentary rocks are classified (dominantly) based on what?

• Grain sorting

• Grain size

• Grain compositions

• Depositional environment

A sedimentary rock which contains environmental clues, such as well sorted sandstone with reddish coloring from oxidation and >1 meter (3ft) cross-beds, would mostly likely indicate which depositional environment?

• River sand dunes

• Glacial sand dunes

• Aeolian (wind-blown), desert or coastal sand dunes

• Deep ocean sand dunes

A sedimentary rock which contains environmental clues, such as grey-green mudstones with laminations and freshwater fossils, would mostly likely indicate which depositional environment?

• delta

• River

• Shallow marine

• Aeolian

• Lacustrine (lake)

Sediment with sharp angular clasts usually implies:

• deposition of the sediment far from the source

• not much abrasion has occurred and short transport distances

• sediment with clasts of about the same size and uniform energy in the environment of deposition

• a source that only contained one type of mineral

Which is NOT considered a transitional depositional environment?

• lagoon

• lake

• beach

• delta

For clastic sedimentary rocks, what is NOT a general trend in the grain characteristics as sediment get transported farther away from the sediment's source rock?

• Sediment grains get more rounded/smoother, less angular.

• Sediment grain size gets smaller.

• Sediment grain size range gets bigger, so more poorly sorted.

What is one of the main agents involved in creating minerals in chemical sedimentary rocks, is a universal solvent, and is a weathering and erosion agent that produces grains of sediment?

• water

• glaciers

• organisms

• wind